Botulinum toxin type A is effective in treating neurologic entities with increased muscle tone. Few reports show the benefits of this treatment for orthopedic conditions. We present the case of a 54-year-old man who manifested bilateral pectoralis major stiffness and bilateral shoulder pain; he had a score of 6 on a visual analog scale (VAS). Complex regional pain syndrome (type I) after cardiac surgery, which had already been resolved, was significant in the patient's clinical background. On examination, neither increases in muscle tone nor signs of tendinous or joint pathology was found. However, the patient experienced significant pain when both pectorals were stretched. The patient's Constant score, a validated scale of shoulder function, was 45/100 on the right shoulder and 41/100 on the left. The patient's shoulder stiffness and pain neither responded to rehabilitation (stretching exercises, passive mobilization, electrostimulation) nor to oral medication (alprazolam, gabapentin). Despite the lack of increased muscle tone, we decided to administer botulinum toxin type A to control pain. Subsequently, pain intensity was reduced to 4 on a VAS on both sides, and functionality improved (Constant scale score, 62 on the right side; 60 on the left). This improvement enabled the patient to resume his job as a building supervisor, which required active involvement in physical construction work.